From 2c8897953f3b2ff5498f3f275708a742bfcdbc24 Mon Sep 17 00:00:00 2001 From: Paul Blakey Date: Wed, 6 May 2020 14:24:39 +0300 Subject: netfilter: flowtable: Add pending bit for offload work Gc step can queue offloaded flow del work or stats work. Those work items can race each other and a flow could be freed before the stats work is executed and querying it. To avoid that, add a pending bit that if a work exists for a flow don't queue another work for it. This will also avoid adding multiple stats works in case stats work didn't complete but gc step started again. Signed-off-by: Paul Blakey Reviewed-by: Roi Dayan Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_flow_table_offload.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'net/netfilter/nf_flow_table_offload.c') diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c index e3b099c14eff..3d4ca62c81f9 100644 --- a/net/netfilter/nf_flow_table_offload.c +++ b/net/netfilter/nf_flow_table_offload.c @@ -817,6 +817,7 @@ static void flow_offload_work_handler(struct work_struct *work) WARN_ON_ONCE(1); } + clear_bit(NF_FLOW_HW_PENDING, &offload->flow->flags); kfree(offload); } @@ -831,9 +832,14 @@ nf_flow_offload_work_alloc(struct nf_flowtable *flowtable, { struct flow_offload_work *offload; + if (test_and_set_bit(NF_FLOW_HW_PENDING, &flow->flags)) + return NULL; + offload = kmalloc(sizeof(struct flow_offload_work), GFP_ATOMIC); - if (!offload) + if (!offload) { + clear_bit(NF_FLOW_HW_PENDING, &flow->flags); return NULL; + } offload->cmd = cmd; offload->flow = flow; -- cgit